Means for removing particles of suspended matter from bodies of fluid and the like.



W. W. STRONG & A. F. NESBIT.

MEANS FOR REMOVING PARTICLES 0F SUSPENDED MATTER FROM BODIES 0F FLUID AND THE LIKE.

APPLICATION FILED IBB.11, 1913.

1,11 7,531. Patented Nov. 17, 1914.

ED STATES PATENT OFFICE.

WILLIAM WALKER STRONG, OF PITTSBURGH, AND ARTHUR FLEMING NESBIT, 0F WILKINSBURG, PENNSYLVANIA, ASSIGNORS TO B. B. MELLON, OF PITTSBURGH,

PENNSYLVANIA.

MEANS FOR REMOVING PARTICLES OF SUSPENDED MATTER FROM BODIES OF FLUID AND THE LIKE.

Specification of Letters Patent.

Patented Nov. 17, 19.14.

Applicationflled February 11, 1913. Serial No. 747,784.

To all whom it may concern:

Be itknown that we, WIIZLIAM YVALKER STRONG and ARTHUR FLEMING Nnsnrr, citizens of the United States, residing at Pittsburgh and I'Vilkinsburg, respectively, in the county of Allegheny and State of Pennsylvania, have invented new and useful Improvements in Means for Removing Particles of Suspended Matter from Bodies of Fluid and the like, of which the following is a specification.

This invention contemplates certain new and useful improvements in means for removing particles of suspended matter from bodies of fluid and the like, by the application of electrical discharges to the said bodies.

Heretofore electrical discharges have been employed for the purpose of removing suspended matter from fluids, etc., which discharges may consist of brush discharges, the electrical wind, the corona discharge, etc. The nature of these discharges is not Well known, but they involve among other phenomena, secondary ionization of the fluid medium, which may be due to the collision of the ions with the fluid particles, or it may be due to electromagnetic pulses or waves. It is known, however, that electrical discharges of this kind result in a copious production of ions. Any discharge can be effected only by the use of one or more electrodes placed in or near the fluid medium, and the electrical discharge may be caused to take place from one electrode, vwhich is designated as the active electrode. In the art of removing matter from fluids, the electric field may be made very concentrated near the active electrode in order that the luminous, heat and ionization effects may be localized in the neighborhood of the said electrode. The secondary ionization produced in this region results in the production of a large number of positive and negative ions. The ions having charges dissimilar to that of the active electrode are attracted toward it and are said to give up their charge to this electrode as ions of the said sign of charge. Ions possessing a sign of charge that is the same as that of the active electrode are repelled from it and if the secondary ionization is sufliof ions will be designated as a stream of ions, or an electric current.

The object of the present invention is to utilize these phenomena in removing suspended matter t'rom fluids, etc., by passing the latter between an active electrode, the latter being shaped to secure the desired results.

A further object is to produce a separating apparatus which is particularly adapted for use in tunnels and the like.

The invention will be hereinafter fully set forth and particularly pointed out in the claims.

In the accompanying drawing :Figure l is a transverse sectional view of a separating apparatus embodying our invention, the electric circuit, source of energy, etc., being illustrated diagrammatically. Fig. 2 in a side view with a simple electrical circuit shown. Fig. 3 is a transverse sectional view of a modification of Fig. 1. Fig. 4 is a similar view of another modification. Fig. 5 1s a diagrammatic view illustrating another modified form of separating cell. Figs. 6, 7 and 8 are diagrammatic views illustrating the action of the electrode.

We wish to have it understood that our electrical circuits are made up of such combinations of series and parallel groupings and a grounded of resistances, inductances, capacities and of a transformer 12. The high potential coil 1: of the transformer may be connected as shown in the figures with a suitable rectifying device 15, the same being utilized for maintaining the potential of the active electrodes 16 unipolar. It will be understood, however, that we do not desire to limit ourselves to the use of a unidirectional current, or to the use of a rectifier, although we prefer to use the same. In Fig.1 the grounded electrode is illustrated as formed of oppositely disposed members 17, 18 placed one above the other. and each formed with lateral branches 19 extend ing in opposite directions. said lateral branches being also curved downwardly. Each member 17, 18, is provided with a plurality of spaced apart bulged portions 20 connected by intermediate straight walls 21, said bulged portions and connecting walls coiiperating to form a. plurality of approximately cylindrical cells connected by constricted passage ways, the active electrodes 16 being centrally disposed in said cells. It will be noted that the member- 17' is provided with spaced apart parallel walls 22 forming an entrance conduit for the separating apparatus, the member 18 being provided with two of the bulged portions 20 immediately over the top of said ,conduit. We do not desire to be limited in this particular, however.

In operation, the plates or walls 22 ex tend low enough for the smoke stack of a locomotive or the like to pass between them, the grounded electrode or separating device being secured to the ceiling of a tunnel, or the like. As the smoke emitted by said stack enters the conduit 22 it passes laterally to both sides and successively through the various cells 20 and constricted passages until discharged at the outlet ends of the grounded electrode. In their passage through the space between the members 17, 18, the suspended particles will fall upon said member 17 from whence they may be removed in any suitable or preferred manner. If desired, the bottom wall 17 may be omitted, as illustrated in Fig. 3 in which event the suspended particles are attracted to the upper electrode or member 18. Or said. member 17 may be made of w1re net or gauze as indicated in Fig. 4 at 17'. In lieuof forming the separating cells in the manner shown and described. above, the same may be made in the form of a frustum of a cone, as illustrated at 23, Fig. 5. The purpose of providing the grounded electrode with oppositely extending passageways or arms is to provide a symmetrical form of precipitator adapted to fit into the arch of a conduit or tunnel, and at the same timeexpose a large amount of electrode. y

In practice, irrespective of what the direction of travel may be the fluids subjected to the ionic currents are wholly or partly cleaned of their solid and liquid matters held in suspension, the latter being deposited upon the inside surface of the grounded electrodes. When suflicient matter has been deposited upon these surfaces to provide for a gap for a disruptive discharge to pass, sparking takes place, and this causes more or less of the precipitated matter to be loosened from the electrode. The portions of the deposited. matter thus loosened fall down through the cell. In this method of cleaning the electrodes it is necessary to have certain predetermined relations between the capacity, self-induction, and resistance factors of the high tension circuit so that the discharge is disruptlve when the distance between the electrode 16 and the deposited grounded surface to the active For the purpose of producing disruptive oroscillatory discharges various suitable conditions may be imposed upon the electrical circuits connected to the active and grounded systems of electrodes. For the purpose of illustration, beside the resistance, capacity, and self induction of the transformer itself, we have shown in Fig. 2 certain combinations of resistances 24,25, capacities 26, 27, self-indnctances 2-8, 29 and spark gaps 30, 31, distributed in the secondary circuit, so that nndcrworkin'g conditions electromagnetic oscillations of the proper frequency and damping factor are produced. These resistances, capacities, self-inductances and spark gaps are placed in whatever parts of the circuit found most suitable or desirable for the results desired, and for obvious reasons we do not limit ourselves to the precise arrangement illustrated. Among tive force; the frequencv of these phasesmay have any suitable value and need not be of the same value. Thus one phase may have the value of its capacity, self inductance and resistance such that a discharge due to this phase would be disruptive or oscillatory in nature, while the discharges of the other phases could be of a flammatory or arc-like character. The impression of these electromotive forces and current-waves need not be simultaneous and may be eifected by independent electrical circuits. In a like manner the phase relation between the current and electromotive force waves of any circuit may be regulated so as to produce disruptive or oscillatory discharges, and by this means effect the removal of matter contained in the fluids subjected to the action of the electrodes. It is obvious, however, that the deposited matter may be removed from the electrodes in any other suitable manner, for instance by causing the latter to vibrate under the stroke of a hammer or the like, whereby the adhering particles are dislodged.

It has been found experimentally that when precipitating the so-called smoke from soft coal furnaces, there is considerable ash and tar carried along with the soot (or carbon) and on account of the high tempera ture of these ingredients, more or less adheres to the central or active electrode and also to the inner walls of the grounded electrode. The actual conditions which have been met may be illustrated by reference to Figs. 6, 7, and 8. In Fig. 6 the active electrode 16 is shown as having a deposit, which for the sake of illustration may be taken as about of an inch in radial depth at the position a and at the positions 6 and 0 somewhat less. .A soon as the distance at the point a between the electrode 17 and the deposited matter has been reduced by accumulations upon the electrode 16, to such a value that a disruptive discharge takes place, a momentary spark passes, and simultaneously with the occurrence of this spark the deposit on the actual electrode between the planes at and y and u, 'v, is violently dislodged and settles into the chamber below. (See Fig. 7). At the same time a large patch of the comparatively thin deposit on the inner wall of the grounded electrode would become detached from the latter and breaking into small pieces also fall into the deposition chamber. The next disruptive discharge would in all probability take place in succession at such positions as b and o-respectively. It has been our experience that such de osit might accumulate once in an hour, wit very tarry smoke, and within erhaps a minute or two, the active electro e 16, throughout its entire length would have dislodged the deposit that had formed upon it. It has also been observed that the corona formation remains remarkably uniform, radially about the entire length of the active electrode, even though the radial depth of the deposit may vary as suggested in Fig. 6. At the points where the disruptive discharge is about to take place, the reater radial depth of the deposit tends to t in out the corona glow as ob served by the eye, and at the same time causes no apparent diminution of the corona elsewhere along the electrode 16.

The peculiar property possessed by an electric arc, that the potential difference across its terminals increases as the current through it decreases, may be utilized to produce electric oscillation.

The grounded electrode 17 is shown to be the collecting electrode, in the drawing,

the (Sheet of making it such being to minimize t e amount of insulation necessary for the bulky parts of the electrodes and at the same time properly control the flow of gases, etc. which may be admitted. The electrode 16 1s called the active electrode because the electric fieldand consequent ionization is most intense at the surface of this electrode.

Having thus explained the nature of our invention, and described an operative manner of constructing and using the same, although without attempting to set forth all of the forms in which it may be made, or all of the forms of its use, what we claim 1s 2- 1. An improvement in means for removing suspended matter from bodies of fluid and the like, comprising a grounded electrode having oppositely extended passage ways for said bodies, active electrodes arranged in juxtaposition to said grounded ing suspended matter from bodies of fluidand the like, comprising a grounded electrode having oppositely extended arms each provided with spaced apart bulging portions connected by intermediate walls, active electrodes disposed opposite said bulging portions, and means for maintaining said electrodes at a high difference of potential.

3. An improvement in means for removing suspended matter from bodies of fluid and the like, comprising a grounded electrode having oppositely extended arms each provided with a plurality of cells connected by passage ways, active electrodes in said cells, and means for maintaining said electrodes at a high difference of potential.

4. An improvement in means for removing suspended matter from bodies of fluid and the like, comprising a grounded electrode having oppositely extended arms each rovided with a plurality of cells connected y tapering passage ways, active electrodes in said cells, and means for maintaining said electrodes at a high difference of potential.

5. An improvement in means for removing suspended matter from bodies of fluid and the like, comprising a grounded electrode having an inlet assage and o positely extended lateral discharge members communicating with said passage, active electrodes extending into said grounded electrode, and means for maintaining said electrodes at a high difference of potential.

6. An improvement in means for removing suspended matter from bodies of fluid and the like, comprising a grounded electrode having oppositely extended arms and an inlet between said arms, active electrodes passing through said arms, and means for maintaining said electrodes at a high difference of potential.

7. An improvement in means for removing suspended matter from bodies of fluid and the like, comprising a grounded electrode having oppositely extended arms and depending plates, the latter forming an inlet passage, active electrodes passed through said arms, and means for maintaining a high. difference of potential between said electrodes.

In testimony whereof we have hereunto set our hands in presence of two subscribing witnesses.

WILLIAM WALKER STRONG.

ARTHUR FLEMING NESBIT. Witnesses:

THOMAS S. CA N,

W. J. Moons. 

